Vacuum extraction monitoring

ABSTRACT

The invention provides technical advantages as a system, device and method that enables a fetal extraction monitor that is used to monitor fetal heart rates to also monitor a vacuum pressure in a vacuum device.

RELATED APPLICATIONS

The present invention is a divisional of and claims priority from toco-pending U.S. patent application Ser. No. 09/727,124, entitled VacuumExtraction Monitor with Attachment For Hand Pump also by Dr. VictorVines, filed on Nov. 30, 2000.

TECHNICAL FIELD

The invention relates to business methods, and more specifically, theinvention relates to business methods that reduce liability exposure forphysicians that perform vacuum extraction deliveries.

STATEMENT OF A PROBLEM ADDRESSED BY THE INVENTION

When operative vaginal deliveries are necessary, there are presently twooptions—forceps extraction, or vacuum extraction. Vacuum extraction inlabor/delivery suites has become a well-accepted and commonly performedform of vaginal delivery because it may be less hazardous to the motherand fetus than forceps extraction. However, there is the potential forharm to the fetus from prolonged suction application to the fetal head.In addition, there are guidelines governing the amount of vacuumpressure that should be applied to the fetal head, as well as guidelinesregarding the duration of time that the vacuum pressure is applied tothe fetal head during vacuum extraction (these guidelines are printed bythe manufacturers of vacuum devices, and are also available in medicalliterature).

Exemplary effects of vacuum extraction on an infant during deliveryinclude: fetal hypoxia, retinal hemorrhage, chignon, scalp marking andabrasion, cephalhematoma and subcutaneous hematoma, neonatal jaundice,intra-cranial hemorrhage, shoulder dystocia, and subgaleal hemorrhage.Subgaleal hematoma is a particularly dangerous condition. Subgalealhematoma is formed when bleeding occurs into the potential space beneaththe aponeurosis of an infant's scalp. It may be a life threateningcondition for a newborn baby, and is often considered the most seriouscomplication associated with the vacuum extraction. One dangerassociated with subgaleal hematoma arises because the subaponeuroticspace stretches over the whole part of the cranial vault of the infant,and a large proportion of the baby's blood volume can accumulate in thisspace (typically, from damage to the emissary veins). Although subgalealhematoma may occur after forceps and natural deliveries, incidents ofsubgaleal hematoma are increased considerably in vacuum extractionssince the introduction of the vacuum device pulls the aponeurosis fromthe cranium and may injure the underlying veins. Furthermore, becausehemorrhaging into the subgaleal space may occur slowly, and for severalhours following delivery, bleeding into the subgaleal space may bedifficult to initially detect.

Accordingly, there are occasions when a fetus does poorly during orafter vacuum extraction. Whether or not proper guidelines were followedduring the delivery process, sometimes a legal claim is made against adoctor, hospital, nurses, and others associated with the delivery,alleging that the guidelines regarding the use of the vacuum device werenot followed. The present invention provides a solution for reducing thevalue of a claim against those associated with a fetal delivery, andalso reduces the likelihood of an erroneous claim being filed againstthese persons.

SELECTED OVERVIEW OF SELECTED EMBODIMENTS

The invention provides technical advantages as a system, device andmethod that enables a fetal extraction monitor that is used to monitorfetal heart rates to also monitor a vacuum pressure in a vacuum device.One embodiment of the invention is a vacuum extraction monitoring systemfor aiding a person who is assisting with fetal extraction. The systemincludes a suction device that is enabled for vacuum attachment to afetus, a pump that is capable of producing a vacuum pressure, a tubingthat fluidly couples the suction device to the pump, a means fordetecting a vacuum pressure coupled to the suction device, and a fetalmonitor for automatically displaying a vacuum pressure, the fetalmonitor being coupled to the means for detecting a vacuum pressure. Inanother embodiment, the invention is a method of aiding a person who isassisting with fetal extraction. The method includes attaching a suctiondevice to a fetus by placing the vacuum device on the fetus and theninducing a vacuum pressure in the suction device, detecting the vacuumpressure, and automatically displaying the vacuum pressure on a fetalmonitor.

Of course, other features and embodiments of the invention will beapparent to those of ordinary skill in the art. After reading thespecification, and the detailed description of the exemplary embodiment,these persons will recognize that similar results can be achieved in notdissimilar ways. Accordingly, the detailed description is provided as anexample of the best mode of the invention, and it should be understoodthat the invention is not limited by the detailed description.Accordingly, the invention should be read as being limited only by theclaims.

BRIEF DESCRIPTION OF THE DRAWINGS

Various aspects of the invention, as well as an embodiment, are betterunderstood by reference to the following EXEMPLARY EMBODIMENT OF A BESTMODE. To better understand the invention, the EXEMPLARY EMBODIMENT OF ABEST MODE should be read in conjunction with the drawings in which:

FIG. 1 provides a block diagram of a vacuum device, illustrating systemsincorporated by the invention;

FIG. 2 provides a more detailed block schematic of a vacuum device;

FIG. 3 provides a flowchart of a recording algorithm which illustratesone embodiment of the invention;

FIG. 4 illustrates a block flow diagram of a vacuum device algorithmthat implements one embodiment of the invention;

FIG. 5 provides a block diagram of an adapter assembly which providesexisting vacuum devices the features of the invention, and isaccordingly another embodiment of the invention;

FIG. 6 illustrates a pump attachable device capable of attachment to anelectrical pump;

FIG. 7 as a tube attachable device; and

FIG. 8 illustrates a pump attachable device configured to attach to ahand pump, such as a KIWI hand pump.

AN EXEMPLARY EMBODIMENT OF A BEST MODE

The invention allows physicians to measure and record the amount ofpressure and the duration of pressure applied to a fetus' head duringvacuum extraction, it enables improved communication between the nurseand delivering physician thus improving the safety of the vacuumassisted delivery, and the invention lowers litigation costs because apermanent record of vacuum pressures applied during delivery is created.Accordingly, the invention provides systems, devices, and methods foraiding a person who is assisting with fetal extraction. The invention isattachable to a vacuum device, and may incorporate a vacuum device.Furthermore, the pressure inside the vacuum device is monitored andrecorded by a recording device.

Preferably, the invention provides at least the features of monitoringand recording pressures in a suction device used for vacuum-based fetalextraction. Accordingly, FIG. 1 provides a block diagram of a vacuumdevice 100, illustrating systems incorporated by the invention. A pump110 which could be a manually activated hand pump, an electric pump, orany other type of air pump, is fluidly coupled to a suction device 120.The suction device 120 is attachable to a fetus, being preferablyattachable to fetal head. The suction device 120 is preferably a cup,such as a SILC, a SILASPIC, a SOFT-CUP, or a MALMSTROM-type cup, forexample. Fluid coupling between the suction device 120 and the pump 110may be accomplished by a tube 112, and is preferably a plastic tube.

A recording device 130, which may be a monitor, an enhanced monitor, ora custom-developed device for example, provides a user the ability tomonitor air pressures and record air pressures. Accordingly, airpressures may be measured in the monitor 130, or in the tube 112, or inthe pump 110. Furthermore, in FIG. 1, a cable 116 couples the tube 112to the monitor 130. Accordingly, in this embodiment, an air pressure isdetected in the tube 112 and converted into information by a device suchas a transducer. Next, the detected pressure is passed as informationalong the cable 116 to the monitor 130.

With an initial understanding of the vacuum device 100, one may gain abetter understanding of the invention by referring to a more detailedblock schematic. Accordingly, FIG. 2 provides a more detailed blockschematic of a vacuum device 200. The vacuum device 200 has a pump 110in fluid communication with the suction device 120 through a tubing 112.The tubing 112, although not illustrated, may contain therein a wire forcoupling the pump 110 to the suction device 120 (to provide a devicewhich may support traction tension between the pump 110 and the suctiondevice 120). A coupling 114 is shown dividing the tubing 112. However,it should be understood that the coupling 114 need not be intrusive ofthe tubing 112, and could be embodied as a cap/tap, for example. In anyevent, the coupling is enabled to detect the pressure in the tubing(whether the pressure is actually detected in the tubing 112, thesuction device 120, or the pump 110). Preferably, the coupling 114 is aplastic tube with a transducer therein. Although not shown in FIG. 2, atransducer in the coupling detects a pressure, and then produces amechanical or electrical signal based on the pressure detected, or othertransportable signal based on the detected pressure (such as a wirelessradio frequency communication).

The cable 116 provides a commutative connection between the coupling 114and a pressure gauge 132 located in the recording device 130. Of course,although the pressure gauge 132 is illustrated as being located in therecording device 130, the pressure gauge 132 could in fact be located inthe coupling 114, or along the cable 116. Thus, the pressure gauge 132functions as a mechanical or electrical signal receiver, whichtranslates a mechanical signal, or electrical signal, or a wirelesssignal into data that is associated with a pressure.

A processor 140 was coupled to the pressure gauge 132, and provides ameans for processing data from the pressure gauge 132 and associatingthat data with various tables, algorithms, and other information.Furthermore, processor 140 may drive other systems such as a display136, a printing device 138, warning system 144, or a safety system 142,or send information to a recording device 134. Preferably, the processoris a digital signal processor (DSP), a Pentium processor, or a StrongArm processor, for example. The processor 140 retrieves various tables,algorithms, and other information from the recording device 134, thatpreferably stores an electronic record. Preferably, the recording device134 is embodied as memory, such as RAM, ROM, or removable memory such asFlash RAM, a Memory Stick, or a CD ROM.

The display 136 provides real time information, such as pressures overtime, dangerous conditions detected (or other information) to personsassisting with the extraction of the fetus. Preferably, the display 136is a cathode ray video screen, or a plasma screen.

The printing device 138 provides the ability to print numbers or graphsindicating a pressure over time, progressive pressures detected overtime. Preferably, the printing device 138 generates these prints onpaper. Furthermore, although illustrated as being integrated into therecording device 130, it should be understood that the printing device138 may be located externally from the recording device 130.

The safety system 142 causes the implementation of a safety pressurerelease valve preferably located on the pump 110. When triggered, thesafety system 142 may release some of the pressure, or all of thepressure thus returning the pressure inside the tubing 112 to the localatmospheric pressure (or room pressure). The safety system 142 may beembodied as software algorithm for execution in memory, or as mechanicaldevice.

The warning system 144 is for producing a warning when a predeterminedpressure or pressures are detected. Typically, the predeterminedpressure will be a vacuum pressure, which is lower than a predeterminedvacuum pressure, such as 0.2 kgms/cm²-0.8 kgms/cm², depending on thestage of delivery. The warning may be embodied as a light, a sound, or avoice, for example. A light may flash at different rates, or presentdifferent colors, or present different intensities as pressure changesin the tube. Similarly, a sound may change in tone as differentpressures are detected, or a voice may verbally indicate a pressure or awarning condition. Furthermore, the warning system may be used totrigger and provide information to the safety system 142.

A better understanding of the invention may be achieved by examining theoperation of the invention. FIG. 3 provides a flowchart of a recordingalgorithm 300. First, in a record pressure act 310, the recordingalgorithm 300 records a pressure, which exists in a vacuum device. Then,in a store recorded pressure act 320, the recording algorithm 300creates a permanent record of the pressure which was recorded in therecord pressure act 310.

An even better understanding of the invention may be realized byexamining the processes flow of a vacuum device embodied according tothe invention. Accordingly, FIG. 4 illustrates a block flow diagram of avacuum device algorithm 400 that implements one embodiment of theinvention. The vacuum device algorithm 400 comprises a pump algorithm402 for illustrating acts performed with a vacuum device pump, and amonitor algorithm 405 illustrating acts associated with a recordingdevice. The vacuum device algorithm 400 begins in a pump algorithm 402.

The pump algorithm 402 is initiated in an engage monitor act 410. Theengage monitor act may include attaching a cable between a vacuum pumpand a recording device, and then turning on the recording device. Afterthe engage monitor act 410, the pump algorithm 402 proceeds to an applysuction device act 415 in which a suction device is attached to a fetus,and preferably a fetal head. It should be noted that in the applysuction device act 415, if a disposable MITYVAC is being used in theprocedure, adapters should be attached to suction tubing of the vacuumdevice and the disposable MITYVAC assembly. Prior to applying thesuction device to the fetus, the apply suction device act 415calibrates, or zeros, the monitor so that the pressure detected prior toapplying a vacuum to the fetus is recognized as being the localatmospheric pressure. Likewise, prior to the application of a vacuum toa fetus, the monitor is initialized, or “zeroed,” to local atmosphericconditions.

Following the apply suction device act 415, the pump algorithm 402proceeds to an initiate vacuum act 420. In the initiate vacuum act 420 avacuum pressure is created in the vacuum device by manually actuating amanual pump, or by engaging the vacuum switch or trigger in an electricpump. The next act in the pump algorithm 402 changes the vacuumpressure. This is accomplished in an alter vacuum pressure act 425, andis typically employed as a result of a response received from themonitor algorithm 405. Of course, altering the vacuum pressure may notbe necessary during a vacuum extraction procedure, and thus the altervacuum pressure act 425 should especially be viewed as an optional actfor the present embodiment (although the only needed acts are explicitlyarticulated in the claims).

Next, a disengage vacuum act 430 is performed when the pressure in thevacuum device is returned to at least local atmospheric pressure.Furthermore, the pressure may be raised to a pressure greater than localatmospheric pressure to encourage the suction device to separate fromthe fetus. Then, the vacuum device algorithm 400 and pump algorithm 402end together in a remove suction device act 435, in which the suctiondevice is removed from the fetus. Furthermore, in the remove suctiondevice act 435 the recording device may be disengaged, and the record ofthe pressures detected during the vacuum device algorithm 400 may bestored in a permanent medical record, which may be a physical paperrecord and/or an electronic record.

The monitor algorithm 405 initiates in a detect pressure act 450, whichbegins in response to the initialization of the recording device in theengage monitor act 410. In the detect pressure act 450 a pressure in thevacuum device is detected, which will typically be between a room (oratmospheric) pressure and vacuum pressure (meaning a pressure lower thanthe local atmospheric pressures). Next, the vacuum device algorithm 400continues to a record pressure act 455. In the record pressure act 455the pressure detected in the detect pressure act 450 is automaticallyrecorded (or stored), preferably by an electronic means (such as amemory) or by a paper means. Furthermore, the record pressure act 455may include the displaying of the recorded pressure on a monitor orother display.

The recorded pressures are monitored and processed in a process recordedpressure act 460. The process recorded pressure act 460 evaluates thedetected pressure in a warning system, and may direct the displaying orprinting of additional information in response to the warning system.[The process-recorded pressure 460 may include a sub-act of displayingthe processed information on the display device, such as a monitor.]Likewise, if the process is recorded at 460 determines if the detectedpressure exceeds a predetermined pressure, the process recorded pressureact 460 may direct a pressure change, such as a lower pressure, or animmediate return to local atmospheric pressure, in a direct pressurechange act 465. The direct pressure change act 465 produces theelectrical or mechanical signals needed to implement the alter-vacuumpressure act 425.

The invention provides the ability to accurately measure, record, andtrace pressure events that transpire in a vacuum device during vacuumextraction. Accordingly, the invention assist physicians, hospitals, andother delivery personnel in the defense of accusation that properguidelines were not followed during the vacuum extraction. Furthermore,those who suffer from improper vacuum extraction also have access to apermanent medical record, which should facilitate mediated settlements,and avoid the costs of lengthy discovery and emotionally scaringlitigation. Also, because data will be collected with each vacuumextraction, the guidelines for the conduct of a vacuum extraction may bechanged and improved to more accurately be able to predict safeguidelines for a vacuum extraction delivery.

It will sometimes be advantageous to provide existing vacuum devices theability to access the advantages provided by the invention. FIG. 5provides a block diagram of an adapter assembly 500, which providesexisting vacuum devices access to advantages of the invention, and isaccordingly another embodiment of the invention. The adapter assembly500 comprises a pump 510 fluidly coupled to a suction device 520 by atubing 525. A display device 530 is connected to the pump 510.Preferably, the display device 530 is coupled to the pump 510 via anadapter to the pump 510. Better understanding of the adapter assembly500 may be achieved by examining specific embodiment.

FIG. 6 illustrates a pump attachable device 600 capable of attachment toan electrical pump 655. The pump attachable device 600 has an adapter610, such as the threaded fittings illustrated in FIG. 6. Furthermore,the pump attachable device 600 has a pressure transducer 620, whichdetects a pressure and converts the detected pressure to a mechanical orelectrical signal capable of being transferred to a monitor (not shown)via a cable 630. The cable 630 includes a plug 635 capable of attachmentto a monitor or other recording device.

Also, illustrated in FIG. 6 is a pump system 650 having a pumpattachable device attached thereto. The pump system 650 includes anelectric pump 655 such as a MITYVAC, or disposable MTFYVAC, for example.The electric pump 655 has a front end 665, which has a cavity forsupporting other devices and for transporting the pressures, includingthe vacuum pressure, created by the electric pump 655.

The front end 665 has thereon a pressure gauge receiver 660. Typically,the pressure gauge receiver 660 accepts a pressure gauge thatmechanically detects a pressure, which is then displayed for thoseperforming the vacuum procedures. In operation of one embodiment of theinvention, the pressure gauge is removed from the electric pump,typically by unscrewing the pressure gauge, and the pump attachabledevice 600 is then inserted into the pressure gauge receiver 660. Alsoprovided by the front end 665 is a pressure release valve 670. Thepressure release valve 670 allows the inflow of air into the front end,and particularly into the cavity of the front end, in order to increasethe pressure in the vacuum device.

Another embodiment of the invention is illustrated in FIG. 7 as a tubeattachable device 700. The tube attachable device 700 includes a firstend 705, and a second end 707. The first end 705 is preferablyconfigured to either attach to a plastic tube section, or a suctiondevice. The second end 707 is preferably configured to attach to a tube,or a front end such as the front end 765 that is adapted to receive thesecond end 707. The tube attachable device 700 includes tubing 740,which is preferably plastic tubing.

The tubing 740 includes a pressure gauge receiver 760. Accordingly, atransducer/pressure gauge 720 is inserted into the tubing 740 andsecured in the tubing by an adapter 710. Furthermore, pressures detectedby the pressure transducer 720 are converted into a data signal that issent to a recording device along a cable 730. The cable 730 alsoincludes a plug 735, which is connectable to the recording devicemonitor 780, or to a second plug 737. The plug 737 couples an extensioncord 738 to a second plug 739. The second plug 739 is also attachable tothe recording device 780 at a plug socket 788.

The vacuum device illustrated in FIG. 7 includes a pump 755, whichprovides a disposable MITYVAC, and a pressure gauge 760, which is fittedinto the front end 765. Thus, the vacuum device provides a physician theadvantage of having a mechanical visual display provided by the gauge760 (thus requiring little change by those who are accustom to viewingthe mechanical gate 760), as well as providing mechanical and electricdisplays and printouts of the recorded pressures while the recordingdevice 780.

The recording device 780 may produce a printed-paper record 782, as wellas a visual display 784. Of course, the printed-paper record 782 or thevisual display 784 may print or display numbers, graphicalrepresentation or other indicia of the pressures being detected in thevacuum device. Furthermore, the recording device 780 provides a warningdevice 786 which could produce a light, sound, or a vocalized recordingof a warning to those assisting with the fetal extraction.

FIG. 8 illustrates a pump attachable device 800 configured to attach toa hand pump 855, such as a KIWI hand pump. The pump attachable device800 includes an adapter 810, such as threading, gaskets, or otherattachments capable of forming a fluid-tight seal, a pressure-recordingdevice 820, such as a transducer, and a cable 830 for communicating adetected pressure to a recording device via a plug 835. The hand pump855 includes a handle 857, which maintains a vacuum cavity 865 therein.The vacuum cavity 865 is fluidly connected to a hose 870 and a suctiondevice 872. The handle 857 also includes a pressure gauge receiver 860.In an unmodified hand pump, the pressure gauge receive 860 accepts amechanical pressure gauge that mechanically indicate a detected pressurein the vacuum cavity 865. In the vacuum device according to the presentembodiment of the invention, the pump attachable device 800 is securedinto the handle 857 of the hand pump 855 via the pressure gauge 860.

Thus, though the invention has been described with respect to a specificpreferred embodiment, many variations and modifications will becomeapparent to those skilled in the art upon reading the presentapplication. It is therefore the intention that the appended claims beinterpreted as broadly as possible in view of the prior art to includeall such variations and modifications.

1. A device for recording a pressure produced by a vacuum extractiondevice, the vacuum extraction device enabled to couple to a fetus via asuction device, comprising: a cable that is attachable to a monitor, themonitor capable of recording a detected pressure; a pressure detectiondevice coupled to the cable, the pressure detection device couples to acavity of a vacuum extraction device for use with fetal extraction suchthat the pressure detection device may detect a pressure in the cavity;the pressure detection device further adapted to communicate a detectedvacuum pressure to the monitor via the cable; the vacuum extractiondevice being adapted to produce a vacuum therein via hand-actuation; andthe vacuum extraction device comprising a suction device being vacuumattachable to a scalp portion of a fetus.
 2. The device of claim 1wherein the tubing has a first end and a second end.
 3. The device ofclaim 2 wherein the first end and the second end are enabled to coupleto tubing.
 4. The device of claim 2 wherein the first end is enabled toattach to a vacuum pump.
 5. The device of claim 2 wherein the first endis enabled to attach to a suction device.
 6. A vacuum extractionpump-attachable device that monitors a vacuum pressure in a vacuumextraction device, comprising: an adaptor enabled to attach to apressure gauge receiver of a hand actuated vacuum extraction device, thevacuum extraction device comprising a suction device adapted to coupleto a scalp portion of a fetus; a vacuum pressure detector secured in theadapter such that the vacuum pressure detector is exposed to an aircavity in the vacuum extraction device; and a cable coupled to thevacuum pressure detector, the cable enabled to attach to a monitor forrecording a detected vacuum pressure.
 7. The pump-attachable device ofclaim 6 wherein the air pressure detector is a transducer.
 8. Thepump-attachable device of claim 6 wherein the monitor is coupled to thecable.
 9. The pump-attachable device of claim 8 wherein the monitor isenabled to display a detected pressure.
 10. The pump-attachable deviceof claim 6 wherein the air pressure detector generates a mechanicalsignal based on the pressure.
 11. The pump-attachable device of claim 6wherein the air pressure detector generates an electrical signal basedon the pressure.
 12. The pump-attachable device of claim 8 wherein themonitor is enabled to generate a paper record.
 13. The pump-attachabledevice of claim 6 further comprising a pressure release valve coupled tothe hand pump.